Apple Color LaserWriter 12/600 PS - Manual (Page 99)

When foreground printing is turned on, you must wait until the document has
finished printing before you can use your computer for other work. However,
your document may be sent to the printer faster when foreground printing is
turned on.
Note: Background printing uses disk space to store your print job. If you have
limited disk space available, you may want to turn foreground printing on.
You can also specify when your document should be printed in relationship to
other documents that are also being printed.
1 Choose Print from the File menu.
The Print dialog box appears.
2 Choose Background Printing from the Settings pop-up menu.
The Background Printing dialog box appears.
3 Make the selections you want.
4 When the selections are as you want, choose another setting from the Settings pop-up
menu, or click Print.
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